Summary — not the spec. This file orients you and links to the authoritative developers.sinch.com doc; it may lag, omit fields, or simplify nesting. Do not copy field names, nesting, encodings, or enums from here into shipped code without confirming them in the linked doc. See "Source of Truth" in this skill's SKILL.md.

SDK Installation (Node.js)

npm install @sinch/sdk-core (v1.4.0+)

ESM vs CommonJS — The SDK uses ESM imports by default: import { SinchClient } from "@sinch/sdk-core". For CommonJS, use const { SinchClient } = require("@sinch/sdk-core").

Project-Scoped Auth (Conversation, Numbers, Fax, EST, etc.)

import { SinchClient } from '@sinch/sdk-core';

const sinch = new SinchClient({
  projectId: 'YOUR_PROJECT_ID',
  keyId: 'YOUR_KEY_ID',
  keySecret: 'YOUR_KEY_SECRET',
});

Setting the Conversation API Region

The region should be set explicitly for Conversation API usage. Not yet enforced in SDK v1 for backward compatibility, but recommended.

import { SinchClient, ConversationRegion } from '@sinch/sdk-core';

const sinch = new SinchClient({
  projectId: 'YOUR_PROJECT_ID',
  keyId: 'YOUR_KEY_ID',
  keySecret: 'YOUR_KEY_SECRET',
  conversationRegion: ConversationRegion.EUROPE, // us, eu, or br
});

Application-Scoped Auth (Voice, Verification)

App credentials only:

import { SinchClient } from '@sinch/sdk-core';

const sinch = new SinchClient({
  applicationKey: 'YOUR_APP_KEY',
  applicationSecret: 'YOUR_APP_SECRET',
});

Combined project + app credentials (multi-product):

import { SinchClient } from '@sinch/sdk-core';

const sinch = new SinchClient({
  projectId: 'YOUR_PROJECT_ID',
  keyId: 'YOUR_KEY_ID',
  keySecret: 'YOUR_KEY_SECRET',
  applicationKey: 'YOUR_APP_KEY',
  applicationSecret: 'YOUR_APP_SECRET',
});